One big issue with replacing your laptop with an iPad is that Apple's tablet doesn't seem to age well. Photo: Apple

I tweeted the other day to no one in particular that I couldn't see my iPad replacing my desktop machine but I could easily imagine not buying another laptop.

I've given it more thought and as much as I had assumed I'd update my MacBook Pro to a MacBook Air in a few years, now I'm not sure I need to. The iPad is now the computer I use most.

The world's reaction to the iPad was muted at first. Like many others, I bought an iPad when it first went on sale in 2010 without a clear idea what I would use it for. Before buying it, I'd played with one for about 30 minutes, firing through 10 to 15 iPad apps in quick succession: the BBC app, Marvel comics, the Guardian photos app, and a graphically rich interactive book.

Steve Jobs mused about whether there was a space for a product between a smartphone and a laptop and decided the iPad was it. According to the Walter Isaacson biography, the polite applause and muted reception depressed Steve Jobs because the concept had been the culmination of several years of work.

Meanwhile, the tablet drew accusations that it was primarily a device for the passive consumption of content. Not anymore. The iPad is selling at pace far in excess of any previous Apple product.

There's no doubt that the iPad is a fine device to watch stuff on. One of the best descriptions comes from the journalist and TV writer Charlie Brooker who described it as a device "ideal for idly browsing the web while watching telly".

It performs this function very well, but two years after I first started to use it, I know it does a whole lot more. So much more that I suspect, based on my personal usage, that I can get by with a desktop Mac and an iPad and cut out Mr Laptop altogether.

Here is my home set-up: a mid-2007 24-inch iMac, a mid-2010 13-inch MacBook Pro and a third-generation 32GB wi-fi iPad. I would estimate my usage ratio as 20:10:70 for iMac:MacBook Pro:iPad.

Lack of a physical keyboard

Some people dismiss the iPad because they feel it's uncomfortable to write on due to its lack of a physical keyboard. But I found you soon get used to it.

I admit that even now I probably make more mistakes on the soft iPad keyboard than I do on a real one, yet these errors do not represent enough of a problem to stop me using it for writing and certainly not when considering the device's wider benefits.

On three occasions I've written full articles in the car - of course, not while driving. There's more room to work on trains with the added bonus that I don't need to worry about being within a couple of feet of a power cord.

For me, the iPad's key work uses are writing and editing articles - sometimes long ones - producing simple presentations, and viewing often tedious papers in preparation for meetings.

I use it as my main email and browsing machine. It's excellent for managing social media channels. There are endless Twitter clients and the WordPress app lets you post articles, review and publish comments and get headline traffic and usage data.

The Pages app is an excellent basic word processor, possibly my favourite since the Windows version of WordPerfect 5.2. Pages is used for making notes in meetings or at presentations, as well as writing longer articles. Note-taking on the iPad also means my jottings are legible, unlike my paper laptop filled with full of page after page of childlike scrawl.

A to-do app lets my manage priorities and a calendar app lets me manage time and appointments. Dropbox lets me access my files from anywhere with a wi-fi connection and presents documents and papers very well, although Excel spreadsheets less so.

Of all the common productivity applications, spreadsheets are the most problematic. I'm not a fan of either the Mac or iPad version of Numbers so still looking for a solution on this issue.

There will be many cases where a laptop is preferable to an iPad. But for someone who needs the basic functions of web, email, social media, productivity apps and other office-based applications, the iPad is starting to look like a worthy alternative.

It offers mobility and lightness, excellent user experience and a superior focus on tasks and work. Plus, in downtime, it's an excellent machine to watch stuff on.

Issue with iPad as laptop replacement

The one big issue I have with the iPad as a laptop replacement is device longevity. My first-generation iPad is becoming slow and unresponsive and despite my new iPad's quick performance I suspect that in two years it will succumb to a similar fate.

iPads don't seem to age well the way Macs do. Given their lower price, I suspect Apple - and possibly other manufacturers - see them as devices that will have a shorter upgrade lifecycle than laptops or desktops.

Despite being a mid-2007 model, my iMac is still in fine shape and will last another couple of years before being upgraded. The MacBook Pro is new and will give many more years of service.

This may be the core issue. A Mac laptop has traditionally lasted me five to six years before being upgraded. If the iPad continues to creep towards obsolescence after two or three, then the maths takes over. Will it be a smaller outlay every two years for a new iPad or a larger investment every five to six years for a new laptop?

However, cost aside, increasingly there's not really an argument for me over form and function. The iPad is winning the day.